After fixing the oil return the to the main tank issue I thought I was done in that area.
Whilst driving the car a little last weekend I noticed a small amount of oil bubbling
at the base of the small oil tank breather filter I installed.
Seeing as the car hadn't been driven far or pushed hard I though that could only get worse under more extreme driving so I have decided to install a oil breather/catch tank.
So I'll route the outlet made for the breather filter to the catch tank and hopefully this should stop any future problems.

Turbo oil return to main tank:

There is an internal 12mm pipe that runs into the main neck of the filler, so the turbo return oil is deposited as far down the neck as I could get it to minimize any getting back up towards the breather filter.